B_c meson production in \gamma\gamma collisions and charm content of the photon

Abstract

Based on photon structure function formalism we have calculated $B_c(B_c^{*})$ meson production cross section in $\gamma\gamma$ collisions via partonic subprocess $c\gamma\to B_c(B_c^{*}) b$. It was shown that this approach gives the same results for $B_c^*(B_c)$ meson cross sections as the direct leading order QCD calculation of the subprocess $\gamma\gamma\to B_c(B_c^{*})b\bar c$ at small energy. Howere, opposite to the direct QCD calculation we have obtained the increase of the $B_c(B_c^{*})$ meson cross section at large energies. We have found also additional contribution to the $B_c$ meson production via the nonperturbative fluctuations $\gamma\leftrightarrow J/\psi$.